﻿#region

using System;
using System.Collections.Generic;
using System.Linq;
using Tateeda.ClinicalStudy.Base.Data.DBModel;
using Tateeda.ClinicalStudy.Base.Data.EF;
using Tateeda.ClinicalStudy.Base.Modules.Infrastructure.Interfaces.Services;

#endregion

#region - Legal -

///<legal>
/// Copyright © 2011, Tateeda Media Network
/// All rights reserved. http://tateeda.com
///
/// Redistribution and use in source and binary forms, with or without
/// modification, are permitted provided that the following conditions
/// are met:
///
/// - Redistributions of source code must retain the above copyright
/// notice, this list of conditions and the following disclaimer.
///
/// - Neither the name of the Tateeda Media Network, nor the names of its
/// contributors may be used to endorse or promote products
/// derived from this software without specific prior written
/// permission.
///
/// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
/// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
/// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
/// FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
/// COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
/// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES INCLUDING,
/// BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
/// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
/// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
/// LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
/// ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
/// POSSIBILITY OF SUCH DAMAGE.
///</legal>

#endregion - Legal -

namespace Tateeda.ClinicalStudy.Base.Modules.Infrastructure.Concrete.Services {

    public class ApplicationService : IApplicationService {
        // local cache user -> time zone info
        private static readonly Dictionary<int, TimeZoneInfo> UserTimezones = new Dictionary<int, TimeZoneInfo>();
        private readonly IUnitOfWork _unitOfWork;

        public ApplicationService() {
            _unitOfWork = new SqlUnitOfWork();
        }

        #region IApplicationService Members

        public virtual IUnitOfWork UnitOfWork {
            get { return _unitOfWork; }
        }

        public virtual Setting FindSettingByName(string name) {
            throw new NotImplementedException();
        }

        public virtual DateTime ConvertTimeFromUTC(int appUserId, DateTime universalTime) {
            TimeZoneInfo destTimeZone = GetTimeZoneInfo(appUserId);
            DateTime time = DateTime.SpecifyKind(universalTime, DateTimeKind.Utc);
            DateTime destTime = TimeZoneInfo.ConvertTimeFromUtc(time, destTimeZone);
            return destTime;
        }

        public virtual DateTime ConvertTimeToUTC(int appUserId, DateTime sourceTime) {
            TimeZoneInfo sourceTimeZone = GetTimeZoneInfo(appUserId);
            DateTime time = DateTime.SpecifyKind(sourceTime, DateTimeKind.Unspecified);
            DateTime universalTime = TimeZoneInfo.ConvertTimeToUtc(time, sourceTimeZone);

            return universalTime;
        }

        public virtual TimeZoneInfo GetTimeZoneInfo(int appUserId) {
            TimeZoneInfo tz;
            lock (UserTimezones) {
                if (!UserTimezones.Keys.Contains(appUserId)) {
                    AppUser user = UnitOfWork.AppUsers.Where(au => au.AppUserId == appUserId).SingleOrDefault();
                    if (user == null) {
                        return null;
                    }
                    Site site = UnitOfWork.Sites.Where(s => s.SiteId == user.SiteId).SingleOrDefault();
                    if (site == null) {
                        return null;
                    }
                    tz = TimeZoneInfo.FindSystemTimeZoneById(site.TimeZoneId);
                    UserTimezones[appUserId] = tz;
                } else {
                    tz = UserTimezones[appUserId];
                }
            }
            return tz;
        }

        #endregion
    }
}